The present invention relates to humidifiers for inhalation therapy, and more particularly concerns a humidifier arranged for use with a source of controlled breathing mixture to provide a humidified breathing mixture.
Hospital patients requiring relatively low flow rates of moisturized breathing mixture of higher oxygen content are often serviced by simple, disposable nebulizers or humidifiers. Such an inexpensive disposable nebulizer is disclosed, for example, in U.S. Pat. No. 5,063,921 to Blair E. Howe for Nebulizer Heater. In the arrangement of this patent, oxygen under pressure is mixed with air to provide a high speed turbulent air stream that entrains water from a water bottle and which is caused to flow through a flow control chamber and over a heater to provide a moisturized heated and oxygen enriched breathing mixture to the patient. However, some patients require higher flow rates of oxygen enriched air for purposes of therapy and cannot be serviced at such high flow rates by conventional nebulizers. Some patients require more complex and selectively variable flow rate control of breathing mixtures. Breathing mixtures of such high flow rates and/or variable control are generally provided in a hospital by complex and expensive equipment known as a ventilator.
Ventilators often involve microprocessor controlled systems, electrically powered and electronically operated. These systems may include connections to wall air and oxygen pressure, but also may include optional internal compressors to supply additional air requirements. Ventilator systems are capable not only of providing air for breathing by the patient but are capable of actually controlling the patient's breathing itself. Humidification of the high flow oxygen air mixture from such ventilators is generally accomplished by auxiliary equipment. Again, the auxiliary equipment itself is highly specialized and expensive. Although that portion of the equipment that is directly connected to the patient is often disposable, it too may be costly.
Accordingly, it is an object of the present invention to provide for humidification of a high flow rate breathing mixture with methods and apparatus that minimize or avoid above mentioned problems.